A dental articulator is a movement simulator with which lower jaw movements can be simulated, which is necessary for the manufacture of tooth replacements, e.g. dentures or bridges.
The main parts of an articulator that are significant in this respect are the lower part and the upper part which carry the lower jaw tooth model and the upper jaw tooth model, and which are joined together in a rotating/sliding joint of which the axis of rotation in the final biting position extends at right angles to the vertical centre plane of the articulator. About this axis of rotation of the rotating/sliding joints, present on both sides in the articulator, the thus formed artificial set of teeth can be opened and closed by swivelling the upper part in the vertical centre plane. Furthermore, protrusive movements, laterotrusive movements and mediotrusive movements can be carried out, such as are made possible by the human jaw bone joint.
There are articulators in which the articular sphere is arranged on the lower part and the associated sliding joint guide is arranged on the upper part. An articulator of this kind is called an "arcon articulator". In contrast a non-arcon articulator is one in which the articular spheres are arranged on the upper part and the sliding joint guide is arranged on the lower part.
Known articulators are distinguished on the one hand between kinds which differ from one another with regard to their principle movement. With most articulators, the lower jaw movement is simulated by moving the upper part and thus the upper jaw.
In a known articulator the swivel/sliding joints are provided as articular heads directed upwards, which are arranged on upright supporting limbs of the articulator and engage in articular recesses open on the underside in articular housings arranged on the upper part. With this known configuration the spherical heads are held in the O-position by means of screws pushing against them.
A similar configuration is provided with another known articulator. In this known configuration the spherical heads are pushed by means of the screws obliquely inwards, at the same time against the lateral guide surface and the Bennett guide surface of the associated articular recess.
The two known configurations are disadvantageous for several reasons. One disadvantage is that the Bennett movement is restricted or at least does not correspond to the anatomical factors of the human body. On the other hand, due to the presence of the screws, very complicated operation is inevitable, e.g. when the articulator is to be adjusted or the upper part is to be dismounted from the lower part. Furthermore these known configurations are unsuitable for adjustable articular guide surfaces, e.g. the lateral guide surface or the Bennett guide surface. In both cases adjustments of the guide surfaces lead to positional differences between the lower part and the upper part.